This 1D digicam captures 2D photographs of issues it will probably’t see
— June twenty fifth, 2025
Sure, the title of this text sounds fairly loopy. However not solely is it fully attainable by way of the lens of physics, however it’s also sensible to attain in the true world utilizing inexpensive components. Jon Bumstead pulled it off with an Arduino, a photoresistor, and an affordable transportable projector.
Right this moment’s digital digicam sensors are the results of a reasonably linear development from a digicam obscura up by way of movie cameras. The sunshine from the scene enters by way of a lens that focuses all of that gentle on the 2D aircraft on the identical time. The digital “sensor” is definitely a complete grid of tiny sensors that every measure the sunshine they obtain. The digicam information these values and reconstructing them provides you a digital picture.
Bumstead’s “digicam” works otherwise and solely information a single level of sunshine at a time. The whole digicam is definitely simply an Arduino Mega 2560 (an UNO additionally works) with a photoresistor. The photoresistor offers a single analog gentle measurement and the Arduino reads that measurement, assigns a digital worth, and passes the information to a PC.
Right here’s the cool half: by solely illuminating one level of the scene at a time, the digicam can report every “pixel” in sequence. These pixel values can then be reconstructed into a picture. On this case, Bumstead used a transportable video projector to offer the illumination. It scans the illumination level throughout the scene because the Arduino collects information from the photoresistor.
Bumstead additionally experimented with extra complicated methods that depend on projected patterns and loads of very fancy math to attain comparable outcomes.
Lastly, Bumstead confirmed that this additionally works when the photoresistor doesn’t have line-of-sight to the scene. In that demonstration, gentle from the scene bounces off a chunk of paper, type of like a mirror. The photodetector solely sees the mirrored gentle. However that doesn’t matter — keep in mind, the photodetector is just seeing a single level of sunshine anyway. Whether or not that gentle got here instantly from the floor of objects within the scene or bounced off paper first, the outcome is identical (simply with a bit much less high quality, as a result of the paper isn’t an ideal reflector).
